Product Description The Rugged Suppressors Obsidian 3 Lug Adapter (OA003) is a black 1/2"-28 thread adapter designed to convert compatible 9mm barrels to a 3-lug interface for quick, repeatable suppressor mounting. It features Rugged&';s patented Go/No-Go gauge to help confirm proper attachment before firing for a more confident, surprise-free shooting experience. Built to 9mm HK specification, this adapter is intended for use with 3-lug mounting systems and is not compatible with .45 ACP. Product Highlights Patented Go/No-Go gauge helps verify correct suppressor attachment 1/2"-28 thread pattern for common 9mm threaded barrels Made to 9mm HK specification for 3-lug style mounting Designed for use with a 3-lug mount system (used in conjunction with OSS&';s 3 Lug Mount per manufacturer description) Durable black finish to match common muzzle and suppressor setups Specs Brand: RUGGED SUPPRESSOR Manufacturer Part Number: OA003 UPC: 859383006709 Product Type: 3 Lug Adapter (Suppressor mount adapter) Thread Pattern: 1/2"-28 Color: Black Compatibility Notes: Made to 9mm HK spec; not compatible with .45 ACP Listed Weight: 0.08 lb (as listed by retailer) Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer.